Condensation of triethyl ester of 1,1,5-pentanetricarboxylic acid (XI) with substituted guanidines XXII - XXIX gave acids II - IX, which were converted into esters XI - XIX. The acid II and the ester XI were obtained as mixtures of positional isomers. Analogously, condensation of the triester XXI with dicyanodiamide gave rise to acid X, whose nitrile group, under conditions of esterification of a carboxyl group, produced iminoether XX. In pharmacological tests for antineoplastic activity the compounds prepared exhibited weaker efficacy than 5-(2-amino-6-hydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acid (I), employed as standard.
三乙酸1,1,5-戊二酸酯(XI)与取代基胍(XXII - XXIX)的缩合反应产生了酸(II - IX),然后转化为酯(XI - XIX)。酸(II)和酯(XI)以位置异构体的混合物形式得到。类似地,三酯(XXI)与二氰二胍的缩合反应产生了酸(X),其腈基在酯化羧基的条件下形成亚胺醚(XX)。在抗肿瘤活性的药理学测试中,所制备的化合物表现出比作为标准的5-(2-氨基-6-羟基-4-氧代-3,4-二氢-5-嘧啶基)戊酸(I)更弱的效力。